[simonrozsival]

Context: #13483
Context: #13486

The _PrepareUpdateAndroidResgen target used the CreateResgenManifest task for one job: writing a placeholder AndroidManifest.xml into a fresh temporary directory, which <Aapt2Link/> uses as ManifestFiles. The file is a two-line constant apart from the package name, so a custom task isn't needed.

This change puts the manifest in a private __ResgenManifest property, written as a CDATA block so it reads as plain XML, and writes it with the built-in <WriteLinesToFile Overwrite="true"/>. $(_AndroidPackage) is inserted without XML escaping because <GetAndroidPackageName/> has already validated it. WriteOnlyWhenDifferent isn't used because the target directory is always newly created.

It removes the task, its <UsingTask/>, and the CRM prefix in Documentation/docs-mobile/messages/index.md. The task had no unit tests and no XA codes.

Output differences:

• The file no longer begins with a UTF-8 BOM.
• Line endings follow Environment.NewLine instead of XDocument's default.

#13483 (CreateTemporaryDirectory → <MakeDir/>) and #13486 (GetExtraPackages → <XmlPeek/>) edit lines next to this change, so whichever merges second will have a trivial textual conflict.

Testing: no local build or test run, to save disk space; this relies on CI. xmllint --noout confirms Xamarin.Android.Common.targets is still well-formed.

[Copilot]

🟡 Changes recommended

The new private MSBuild property __ResgenManifest violates the _Android naming convention and needs renaming to _AndroidResgenManifest, including its Lines reference.

1 open issue

• Rename manifest property to follow the _Android prefix convention · New

What changed in this PR

Simplifies .NET for Android resource generation by replacing a dedicated manifest-writing task with MSBuild’s built-in WriteLinesToFile.

Changes:

• Defines the placeholder manifest in a CDATA property and writes it into the temporary resource-generation directory.
• Removes CreateResgenManifest, its task registration, and its documented diagnostic prefix.

File	Description
src/​Xamarin.Android.Build.Tasks/​Xamarin.Android.Common.targets	Replaces the custom task with inline manifest content and WriteLinesToFile.
src/​Xamarin.Android.Build.Tasks/​Tasks/​CreateResgenManifest.cs	Deletes the obsolete manifest-writing task.
Documentation/​docs-mobile/​messages/​index.md	Removes the retired CRM task prefix.

_{Review effort: Balanced}